1. Technical Field
The present disclosure relates to a method of fabricating a touch panel, especially to a method of fabricating a touch panel that is simple and has high accuracy.
2. Description of Related Art
In today's markets, which offer a variety of consumer electronics products, the touch panel has been increasingly used in personal digital assistants (PDA), mobile phones, notebooks and other portable electronic products, as well as personal computers and digital home appliance systems as a communication interface between users and the electronic devices. When using the touch panel, users can directly operate the electronic devices and make commands through screen objects displayed on the panel, providing a more user-friendly operation interface. In addition, electronic products are currently designed to be light, thin, short and small, and it is therefore desirable to economize the space dedicated to some traditional input devices, such as buttons, keyboards, and mice, in product design. Display devices with touch panels are a current trend, and are one of the key components of all kinds of electronic products.
Conventional touch panels can be categorized into capacitive, resistive or surface wave touch panels in accordance with their detection principle, each having different advantages and disadvantages, and different application fields. The resistive touch panel includes an upper transparent conductive film and a lower transparent conductive film that are superimposed to each other. When the user presses the touch panel, strength of the depression makes the upper electrode connect to the lower electrode, and the touch point position can be calculated through the measurement of the voltage change. The surface wave touch screen has a wave source, usually infrared or ultrasound, on one side of the X-axis and Y-axis of the panel and has a receiver on the other side. When a user touches the panel, the waveform is interfered with, and the interference graph can be captured by the receiver, such that the position can be calculated. The capacitive touch screen provides a uniform electric field at the four corners of the panel, and the touch position can be measured by detecting changes of capacitance of the panel.
Due to the advantages of being dust-proof, and having high temperature resistance and multi-touch capability, conventional capacitive touch panels are widely used in portable electronic products. However, a conventional capacitive touch panel usually includes a stack of at least five films, making it hard to achieve a high light transmission ratio, which may result in low display quality. And, because of its large volume and heavy weight, conventional capacitive touch panels are also difficult to integrate into current electronic devices, which are designed to be thin and light. Moreover, the multilayer stacking structure requires a more cumbersome fabrication process, especially when the sensing conductive films are located on both sides of a transparent substrate, rendering the manufacturing process difficult to upgrade.